Starting price for any player is the opening bid made by the team who bids first for that player. Then the value can be increased by any margin by other teams. Only restriction is that it should be increased by full like from $100,000 to $120,000 or $150,000 but not half like $115,000 or $125,000 (for making the final calculation easy). Also while starting bidding for a player, it should be from a fair starting value which a team thinks appropriate much like McCullum's one.